Video- and audio-conferencing is a technology used for communication over long distances. Due to many problems occurring during call setup and call-management, many solutions require conferencing administrators to setup and administrate the conference. To ease the job of call set-up and conference administration, many large organizations and service providers use a centralized server called a Multi-point Control Unit (MCU). A MCU is a server used to handle calls with multiple participants, or to allow central call management of calls from 2 to n participants.
Administrating the call by only having access to end points (EPs) is not a viable solution due to network access limitation, training and education needed to understand equipment from multiple vendors and different versions from the same vendor. An end point (EP) is defined as the video/audio terminal/telephone or gateway used in a video conference.
By having a centralized server (i.e. MCU), conferencing administrators can control most aspects of the call from one single interface. As most MCUs allow multiple conferences, administrators can also monitor multiple calls from the same interface.
Today, there are systems that help manage end points and MCUs like Polycom GMS, Polycom Conference Suite (also known as Applied Global Technologies (AGT) VCAS) and Forgent VNP—however they do not solve the problem of a single call set-up and management interface. They still require an administrator to understand the different devices on the network.
Polycom GMS allows monitoring of calls between end points only. Polycom Conference Suite (AGT VCAS) allows monitoring of calls at a system by system level.
Forgent VNP allows monitoring of calls and call set-up at a system by system level.
TANDBERG Management Suite allows monitoring of calls at a system by system level.
There are several publications describing different technical aspects of video conferencing.
U.S. Pat. No. 6,157,401 describes a gatekeeper used in a video conferencing system for controlling the alias addresses of EPs logging on the system. It is checked whether an address is a “compound address”, and if so ensure that the MCU allocates conference resources to a video conference among the participants thereby designated.
EP-1359708 describes a method for creating a video connection from a video communication terminal with other participants in a video conference.
US-2003/0147357 describes a method for calling video communication service by video communication terminal and associated message data form. More specifically it describes a method for setting up a videoconference by the use of MCUs and caller convening conference mode.
US-2002/0071026 describes an apparatus and method for incorporating virtual video conferencing environments. More specifically it describes an apparatus and method for determining if a user logging on to the system has designated an alternative environment other than a default environment normally detected by a camera device during the video conference. If this is the case, an environment processor obtains the environment from an environment database, and the video conference apparatus uses the designated environment. If it is not the case, the environment processor sends a listing of the possible environments, and the user can then select the preferred environment from this list. If a user does not wish to select an alternative environment, the default environment will be selected.
U.S. Pat. No. 5,594,725 describes a process and system for videorate control.
US-2002/0036707 describes a method for filtering artifacts from multi-threaded video.
U.S. Pat. No. 6,590,603 describes a system and method for managing streaming data.
These publications describe more or less relevant aspects of video conferencing with regard to the present invention. The latest three publications are included as general background art in the video conferencing technology.
Existing video- and audio-conferencing systems allow you to go into the system and monitor/edit calls. TMS, Forgent VNP and Polycom Conference Suite also allows you to do call setup, but do not handle cascaded MCU connections, or monitoring the conference as one entity—just at a system by system level.
There are multiple problems with using centralized servers (MCUs). They may have large size and cost due to the requirement to handle peek conditions. To handle most conditions MCUs are often over sized compared to average use and conference numbers. This is a requirement to handle peek conditions typically occurring during main business hours. Typically this problem is not due to the size of a single conference, but to the amount of conferences taking place. As point-to-point calls also require management, these must also be routed through the centralized server, requiring resources.
Increased call costs due to placement of server is an important factor. As it is typical to have only a few large centralized servers (MCUs) all calls must be dialled to go to and from the centralized server. For example if the company has an MCU located in London England—if a call is to be made between a location in Sweden and Norway, a call must be made between the site in Sweden and the MCU in London, and another call must be made between the site in Norway and the MCU in London. If there was no centralized management requirement, this call could be made with just one call directly between the sites in Norway to Sweden.
A centralized video- and audio-conferencing server is no different than other servers, in that if the server fails, all calls routed through the server will also fail, i.e. single point of failure.
In regards to the problems described above, the solution according to the invention has the following advantages:
Large size and cost due to the requirement to handle peek conditions is greatly minimized. As no single conference server (MCU) is required, multiple smaller units, or MCUs available directly in some end points can be used. There is also no need to oversize the amount of MCUs as there is much smaller overhead to handle many conferences as point-to-point calls will be dialed direct whereas calls requiring many participants that no single MCU can handle, will be split between many smaller MCU.
As there no longer is a requirement for single points of administration requiring a large MCU, many smaller MCUs can be placed through the business areas of a company, thus reducing the call costs due to placement of servers. Also as many end points have internal MCU capabilities, or calls are only between two systems—no need to dial an external MCU is required, allowing the call to be made directly between the systems in the conference.
Since the solution will work even if some of the MCU are not reachable or down, there is no single point of failure.